kernel/linux.git/drivers/pci/setup-bus.c, branch v6.6.132

PCI: Use resource names in PCI log messages

2026-03-25T10:05:31+00:00

[ Upstream commit dc4e6f21c3f844ebc1c52b6920b8ec5dfc73f4e8 ] Use the pci_resource_name() to get the name of the resource and use it while printing log messages. [bhelgaas: rename to match struct resource * names, also use names in other BAR messages] Link: https://lore.kernel.org/r/20211106112606.192563-3-puranjay12@gmail.com Signed-off-by: Puranjay Mohan Signed-off-by: Bjorn Helgaas Stable-dep-of: 11721c45a826 ("PCI: Use resource_set_range() that correctly sets ->end") Signed-off-by: Sasha Levin

PCI: Fix old_size lower bound in calculate_iosize() too

2025-06-04T12:42:08+00:00

[ Upstream commit ff61f380de5652e723168341480cc7adf1dd6213 ] Commit 903534fa7d30 ("PCI: Fix resource double counting on remove & rescan") fixed double counting of mem resources because of old_size being applied too early. Fix a similar counting bug on the io resource side. Link: https://lore.kernel.org/r/20241216175632.4175-6-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Tested-by: Xiaochun Lee Signed-off-by: Sasha Levin

PCI: Use downstream bridges for distributing resources

2025-04-10T12:37:27+00:00

[ Upstream commit 1a596ad00ffe9b37fc60a93cbdd4daead3bf95f3 ] 7180c1d08639 ("PCI: Distribute available resources for root buses, too") breaks BAR assignment on some devices: pci 0006:03:00.0: BAR 0 [mem 0x6300c0000000-0x6300c1ffffff 64bit pref]: assigned pci 0006:03:00.1: BAR 0 [mem 0x6300c2000000-0x6300c3ffffff 64bit pref]: assigned pci 0006:03:00.2: BAR 0 [mem size 0x00800000 64bit pref]: can't assign; no space pci 0006:03:00.0: VF BAR 0 [mem size 0x02000000 64bit pref]: can't assign; no space pci 0006:03:00.1: VF BAR 0 [mem size 0x02000000 64bit pref]: can't assign; no space The apertures of domain 0006 before 7180c1d08639: 6300c0000000-63ffffffffff : PCI Bus 0006:00 6300c0000000-6300c9ffffff : PCI Bus 0006:01 6300c0000000-6300c9ffffff : PCI Bus 0006:02 # 160MB 6300c0000000-6300c8ffffff : PCI Bus 0006:03 # 144MB 6300c0000000-6300c1ffffff : 0006:03:00.0 # 32MB 6300c2000000-6300c3ffffff : 0006:03:00.1 # 32MB 6300c4000000-6300c47fffff : 0006:03:00.2 # 8MB 6300c4800000-6300c67fffff : 0006:03:00.0 # 32MB 6300c6800000-6300c87fffff : 0006:03:00.1 # 32MB 6300c9000000-6300c9bfffff : PCI Bus 0006:04 # 12MB 6300c9000000-6300c9bfffff : PCI Bus 0006:05 # 12MB 6300c9000000-6300c91fffff : PCI Bus 0006:06 # 2MB 6300c9200000-6300c93fffff : PCI Bus 0006:07 # 2MB 6300c9400000-6300c95fffff : PCI Bus 0006:08 # 2MB 6300c9600000-6300c97fffff : PCI Bus 0006:09 # 2MB After 7180c1d08639: 6300c0000000-63ffffffffff : PCI Bus 0006:00 6300c0000000-6300c9ffffff : PCI Bus 0006:01 6300c0000000-6300c9ffffff : PCI Bus 0006:02 # 160MB 6300c0000000-6300c43fffff : PCI Bus 0006:03 # 68MB 6300c0000000-6300c1ffffff : 0006:03:00.0 # 32MB 6300c2000000-6300c3ffffff : 0006:03:00.1 # 32MB --- no space --- : 0006:03:00.2 # 8MB --- no space --- : 0006:03:00.0 # 32MB --- no space --- : 0006:03:00.1 # 32MB 6300c4400000-6300c4dfffff : PCI Bus 0006:04 # 10MB 6300c4400000-6300c4dfffff : PCI Bus 0006:05 # 10MB 6300c4400000-6300c45fffff : PCI Bus 0006:06 # 2MB 6300c4600000-6300c47fffff : PCI Bus 0006:07 # 2MB 6300c4800000-6300c49fffff : PCI Bus 0006:08 # 2MB 6300c4a00000-6300c4bfffff : PCI Bus 0006:09 # 2MB We can see that the window to 0006:03 gets shrunken too much and 0006:04 eats away the window for 0006:03:00.2. The offending commit distributes the upstream bridge's resources multiple times to every downstream bridge, hence makes the aperture smaller than desired because calculation of io_per_b, mmio_per_b and mmio_pref_per_b becomes incorrect. Instead, distribute downstream bridges' own resources to resolve the issue. Link: https://lore.kernel.org/r/20241204022457.51322-1-kaihengf@nvidia.com Fixes: 7180c1d08639 ("PCI: Distribute available resources for root buses, too") Link: https://bugzilla.kernel.org/show_bug.cgi?id=219540 Signed-off-by: Kai-Heng Feng Signed-off-by: Bjorn Helgaas Tested-by: Chia-Lin Kao (AceLan) Reviewed-by: Mika Westerberg Cc: Carol Soto Cc: Jonathan Cameron Cc: Chris Chiu Signed-off-by: Sasha Levin

PCI: Fix resource double counting on remove & rescan

2024-08-03T06:53:55+00:00

[ Upstream commit 903534fa7d30214d8ba840ab1cd9e917e0c88e41 ] pbus_size_mem() keeps the size of the optional resources in children_add_size. When calculating the PCI bridge window size, calculate_memsize() lower bounds size by old_size before adding children_add_size and performing the window size alignment. This results in double counting for the resources in children_add_size because old_size may be based on the previous size of the bridge window after it has already included children_add_size (that is, size1 in pbus_size_mem() from an earlier invocation of that function). As a result, on repeated remove of the bus & rescan cycles the resource size keeps increasing when children_add_size is non-zero as can be seen from this extract: iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB iomem1: 20000000000-200001fffff : PCI Bus 0000:03 # 2MiB iomem2: 20000000000-200002fffff : PCI Bus 0000:03 # 3MiB iomem3: 20000000000-200003fffff : PCI Bus 0000:03 # 4MiB iomem4: 20000000000-200004fffff : PCI Bus 0000:03 # 5MiB Solve the double counting by moving old_size check later in calculate_memsize() so that children_add_size is already accounted for. After the patch, the bridge window retains its size as expected: iomem0: 23fffd00000-23fffdfffff : PCI Bus 0000:03 # 1MiB iomem1: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB iomem2: 20000000000-200000fffff : PCI Bus 0000:03 # 1MiB Fixes: a4ac9fea016f ("PCI : Calculate right add_size") Link: https://lore.kernel.org/r/20240507102523.57320-2-ilpo.jarvinen@linux.intel.com Tested-by: Lidong Wang Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Mika Westerberg Signed-off-by: Sasha Levin

PCI: Fix typos in docs and comments

2023-08-25T13:15:38+00:00

Fix typos in docs and comments. Link: https://lore.kernel.org/r/20230824193712.542167-11-helgaas@kernel.org Signed-off-by: Bjorn Helgaas Reviewed-by: Randy Dunlap Reviewed-by: Ilpo Järvinen

PCI: Make pci_bus_for_each_resource() index optional

2023-04-05T20:10:09+00:00

Refactor pci_bus_for_each_resource() in the same way as pci_dev_for_each_resource(). This allows the index to be hidden inside the implementation so the caller can omit it when it's not used otherwise. No functional changes intended. Link: https://lore.kernel.org/r/20230330162434.35055-6-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko Signed-off-by: Bjorn Helgaas Reviewed-by: Krzysztof Wilczyński Reviewed-by: Philippe Mathieu-Daudé

PCI: Introduce pci_dev_for_each_resource()

2023-04-04T15:43:52+00:00

Instead of open-coding it everywhere introduce a tiny helper that can be used to iterate over each resource of a PCI device, and convert the most obvious users into it. While at it drop doubled empty line before pdev_sort_resources(). No functional changes intended. Suggested-by: Andy Shevchenko Link: https://lore.kernel.org/r/20230330162434.35055-4-andriy.shevchenko@linux.intel.com Signed-off-by: Mika Westerberg Signed-off-by: Andy Shevchenko Signed-off-by: Bjorn Helgaas Reviewed-by: Krzysztof Wilczyński

PCI: Distribute available resources for root buses, too

2023-02-07T17:36:35+00:00

Previously we distributed spare resources only upon hot-add, so if the initial root bus scan found devices that had not been fully configured by the BIOS, we allocated only enough resources to cover what was then present. If some of those devices were hotplug bridges, we did not leave any additional resource space for future expansion. Distribute the available resources for root buses, too, to make this work the same way as the normal hotplug case. A previous commit to do this was reverted due to a regression reported by Jonathan Cameron: e96e27fc6f79 ("PCI: Distribute available resources for root buses, too") 5632e2beaf9d ("Revert "PCI: Distribute available resources for root buses, too"") This commit changes pci_bridge_resources_not_assigned() to work with bridges that do not have all the resource windows programmed by the boot firmware (previously we expected all I/O, memory and prefetchable memory were programmed). Link: https://bugzilla.kernel.org/show_bug.cgi?id=216000 Link: https://lore.kernel.org/r/20220905080232.36087-5-mika.westerberg@linux.intel.com Link: https://lore.kernel.org/r/20230131092405.29121-4-mika.westerberg@linux.intel.com Reported-by: Chris Chiu Signed-off-by: Mika Westerberg Signed-off-by: Bjorn Helgaas

PCI: Take other bus devices into account when distributing resources

2023-02-07T17:04:25+00:00

A PCI bridge may reside on a bus with other devices as well. The resource distribution code does not take this into account and therefore it expands the bridge resource windows too much, not leaving space for the other devices (or functions of a multifunction device). This leads to an issue that Jonathan reported when running QEMU with the following topology (QEMU parameters): -device pcie-root-port,port=0,id=root_port13,chassis=0,slot=2 \ -device x3130-upstream,id=sw1,bus=root_port13,multifunction=on \ -device e1000,bus=root_port13,addr=0.1 \ -device xio3130-downstream,id=fun1,bus=sw1,chassis=0,slot=3 \ -device e1000,bus=fun1 The first e1000 NIC here is another function in the switch upstream port. This leads to following errors: pci 0000:00:04.0: bridge window [mem 0x10200000-0x103fffff] to [bus 02-04] pci 0000:02:00.0: bridge window [mem 0x10200000-0x103fffff] to [bus 03-04] pci 0000:02:00.1: BAR 0: failed to assign [mem size 0x00020000] e1000 0000:02:00.1: can't ioremap BAR 0: [??? 0x00000000 flags 0x0] Fix this by taking into account bridge windows, device BARs and SR-IOV PF BARs on the bus (PF BARs include space for VF BARS so only account PF BARs), including the ones belonging to bridges themselves if it has any. Link: https://lore.kernel.org/linux-pci/20221014124553.0000696f@huawei.com/ Link: https://lore.kernel.org/linux-pci/6053736d-1923-41e7-def9-7585ce1772d9@ixsystems.com/ Link: https://lore.kernel.org/r/20230131092405.29121-3-mika.westerberg@linux.intel.com Reported-by: Jonathan Cameron Reported-by: Alexander Motin Signed-off-by: Mika Westerberg Signed-off-by: Bjorn Helgaas

PCI: Align extra resources for hotplug bridges properly

2023-02-07T16:54:40+00:00

After division the extra resource space per hotplug bridge may not be aligned according to the window alignment, so align it before passing it down for further distribution. Link: https://lore.kernel.org/r/20230131092405.29121-2-mika.westerberg@linux.intel.com Signed-off-by: Mika Westerberg Signed-off-by: Bjorn Helgaas